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Author Question: Scientists once thought that Earth's primary atmosphere was composed of _____. A) hydrogen and ... (Read 61 times)

michelleunicorn

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on: Jul 27, 2018
Scientists once thought that Earth's primary atmosphere was composed of _____.
 
  A) hydrogen and methane
  B) nitrogen and oxygen
  C) carbon dioxide and methane
  D) oxygen and hydrogen

Question 2

Which of the following is true of Mars?
 
  A) It is about 95 percent of Earth's diameter.
  B) It has a thick atmosphere rich in water vapor.
  C) It is the smallest planet of the Solar System.
  D) It has a heavily cratered crust marked by volcanoes.


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janieazgirl

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Reply #1 on: Jul 27, 2018
Answer to Question 1

A

Answer to Question 2

D


michelleunicorn

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Reply #2 on: Jul 27, 2018
Thank you!


janieazgirl

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Reply #3 on: Jul 27, 2018
Always glad to help...


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